Hi, I am developing an excel plugin and i would like to protect my IP. What do you think the best way to do it? Thanks
Encrypt it. How? No idea. Contact a software company you like and politely ask them how they encrypt their plugins. Maybe there's an off-the-shelf app that does this.
Make the buyer sign a license agreement. People who want to look at your code will do it anyway, no matter how well you try to protect it, but if they violate your license agreement at least you have some legal recourse.
You can password protect your plugins so that no one can access the source code. Of course there is password cracking software available, so just make your password as long and random as you can stand, and yes, write it down.